The recent news that Consumer Reports put the 2010 Lexus GX 460 on its "Don't Buy" list has already impacted the vehicle's future — Toyota has issued a stop-sale order on the $52,000 SUV and commissioned extensive testing to determine the cause of its failure.

The safety warning could also pose a public relations problem for the beleaguered company — the GX is the only vehicle to receive the "Don't Buy" designation since it was instituted last July. Only 11 vehicles have received the less-severe "Not Acceptable" rating since the list began in 1969.

But it's too early to call the GX a failure. That label could come after a couple of years of poor reception. Think more along the lines of the 1971 Ford Pinto. Or the 2001 Pontiac Aztek.

"The Aztek is the only car that I can remember that people would walk by and actually point and laugh at you when you were driving it," says Jake Fisher, a senior automotive engineer at Consumer Reports who has worked in the automotive industry for 14 years. "I remember being parked in it, and people would giggle and point because it was so hideous looking."

The Aztek, GM's first attempt at a crossover vehicle, isn't the only car to elicit such a reaction. The Lincoln Blackwood, the Yugo and the Cadillac Cimarron, in the opinions of the industry experts we sought, also make our list of the worst car flops.

In addition to Fisher, who is also a professional driver, Mike Caudill, an automotive expert for NADA Guides, and Karl Brauer, editor-in-chief at Edmunds.com, contributed to our list of the worst flops in history. Each had his own ideas about what makes a vehicle a flop (the cars on our list must have been sold in the U.S. in mass-production volumes available to any buyer) — Fisher says the Honda Del Sol should be on our list because of its odd looks, poor driving performance and short production run; Caudill disagrees about the relative merits of its performance.

The Ford Edsel is one of those models. Along with the Yugo, Edsel is virtually synonymous with the phrase "automotive failure." It was produced from 1958 to 1960, ostensibly as a way to help create a new, up-market division at Ford Motor Company (Edsel cars cost between $2,500 and $4,000, which was more than Ford-branded cars at the time, but less than the Lincoln-branded cars; Mercury cars were priced about the same). But sales were dismal (84,000 total, about half of the projected rate) and critics lambasted its styling (a unique horse-collar grill, among other things), its reliability and overall quality.

The 1982 Cadillac Cimarron is another frequently mentioned flop. Cimarron was Cadillac's first try at making something small — dealers had requested a fuel-sipper because gas prices had become prohibitively high. The Cimarron was built on an economy-car platform and offered either manual or automatic transmission, with some amenities. But it appealed neither to Cadillac's loyal followers, who appreciated powerful V8s and Cadillac's domestic luxury edge, nor to buyers who favored Europe's luxury brands, whose cars out-handled and out-classed the Cimarron in every way. It was discontinued after just six years of production.

"It came at a time when Cadillac was trying to discover itself, and it was one of the ugliest vehicles they ever could have made," Caudill says. "It doesn't look like what you'd expect a Cadillac to look like. If you look at a Mustang now vs. a Mustang then, you go, 'Wow, cool.' But you don't look at a 1982 Cadillac Cimarron and go, 'Man, I need one of those.'"

Not just any car can be a flop. Most have a combination of a stinted production run, drastically lower-than-projected sales (at least 50 percent lower than expected), and critical and/or popular disdain. It will likely also have poor safety or reliability scores, although that's not a prerequisite. One thing is certain: They all end up costing their makers a lot of money. Ford lost $200 million-$250 million (or $1.55 billion adjusted for inflation) on the failed Edsel venture, according to reports at the time. Years later, Ford also lost millions in settlements paid for lawsuits brought over safety complications with the 1970 Ford Pinto.

The Pinto was Ford's first subcompact car and was successfully redesigned to sell hundreds of thousands of units during its 10-year production run. But it earned a devastating and long-lasting reputation after reports of a faulty gas tank that could burst into flames during rear-end collisions. Hundreds were killed in fire-related accidents, and Ford received scathing criticism when investigators discovered that an inexpensive upgrade would have prevented the problem. All told, it cost Ford more to repair the all the faulty Pintos than it cost to make them in the first place.

The 1984 Pontiac Fiero, too, had combustion problems: chronically low levels of oil in the car's engine led to roughly 200 reported fires and dozens of injuries, according to the National Highway Traffic Safety Administration and GM press releases.

Of course, many "flopped" cars have enthusiastically loyal cult followings: '80s-philes love the Back-To-The-Future-famous DeLorean, and collectors pay thousands of dollars for hard-to-find Edsels. Red Bull even fastened large soda cans to the tops of a fleet of bright-red Suzuki X-90s, ugly-duckling two-seaters that sold for just two years, in order to advertise its energy drink.

Other notoriously "bad" cars weren't really that bad, Fisher says: Maybe they just failed to resonate, or perhaps they were meant to spur something even better down the road. The Cimarron flopped — but it might have helped pave the way for Cadillac's 2010 $35,165 CTS, also a compact luxury sedan, which has re-energized the brand and won rave reviews from critics and consumers alike.

The same goes for GM's first potentially mass-produced electric vehicle, the EV1. While there's virtually nothing redeeming about the odd-looking, unreliable and expensive car, it does have a certain value, Caudill says.

"Sometimes in the automotive industry, you have technologies come out that help other automakers learn what not to do, as opposed to what to do," he says. "You have to applaud General Motors. They gave it a shot."